Shallow snapshots

Shallow copy snapshots allow you to reference data from an entire remote-backed segment instead of storing all of the data from the segment in a snapshot. This makes accessing segment data faster than using normal snapshots because segment data is not stored in the snapshot repository.

Enabling shallow snapshots

Use the Cluster Settings API to enable the remote_store_index_shallow_copy repository setting, as shown in the following example:

PUT _cluster/settings
{
   "persistent":{
      "remote_store_index_shallow_copy": true
   }
}

Once enabled, all requests using the Snapshot API will remain the same for all snapshots. After the setting is enabled, we recommend not disabling the setting. Doing so could affect data durability.

Considerations

Consider the following before using shallow copy snapshots:

• Shallow copy snapshots only work for remote-backed indexes.
• All nodes in the cluster must use OpenSearch 2.10 or later to take advantage of shallow copy snapshots.
• There is no difference in file size between standard shards and shallow copy snapshot shards because no segment data is stored in the snapshot itself.
• Searchable snapshots are not supported inside shallow copy snapshots.